Wliier Cento Uno rear brake cable - threading through TT

[guylimey]

Wliier Cento Uno rear brake cable - threading through TT - any ideas anyone (the plastic sleeving that was there at manufacture is no longer there and there is no internal tubing in the TT to guide either the casing or just the inner wire)? I have tried cotton thread and a vacuum cleaner, cotton thread with a needle and a magnet and both without success Too frustrated to continue at this point and looking for ideas/help. Thank you.